The matching of seal prints is a very important method to identify whether a documents genuine, in the oriental society, especially in the Chinese society. In the Chinese society, a document made by an author shall contain a seal print. While the seal print is identified a genuine print of the original seal owned by the author, the document is deemed genuine; i.e., the document is deemed made by the author.
Although the application of computer systems becomes common in the oriental society, using a computer to automatically identify whether a seal print is genuine, is still under development. Among the technologies already available, several semi-automatic seal print matching systems are widely used by the bank to identify the seal prints printed on the withdrawal slips. To describe such a semi-automatic matching system, the function of the seal prints in the bank practice will be introduced.
While a customer opens a savings account in a bank, the customer shall register his (her) seal print with the bank. The seal print is printed on a "seal print card" and is kept by the bank. When the customer withdraw his money from the bank, he fills a withdrawal slip and chop the original seal on the slip so that the seal print of the seal appears on the slip. The slip is then given to a teller of the bank. The teller matches the seal print on the slip with the seal print as recorded on the seal print card. If the seal prints are identical, the teller allows the withdrawal; Otherwise, the withdrawal is rejected.
While the semi-automatic system is used to help the teller in the identification of the seal print, the seal print of the original seal is recorded in the computer of the semi-automatic matching system. In doing this, the print of the original seal is printed on the seal print card and is then scanned by a scanner. The scanner scans the seal print, converts the image into a digitized format and saves the image data in a computer. When the customer wishes to withdraw his money from the bank, he fills a withdrawal slip and prints a seal print on the slip. The teller then recalls the image of the original seal print from the computer and uses the scanner to scan the seal print on the withdrawal slip. The system displays both the image of the original seal print and the image of the seal print on the withdrawal slip on the screen of the system, with different colors. The teller adjusts the position of the image of the seal print on the withdrawal slip with the help of a mouse, or merely by means of moving the withdrawal slip in relating to the scanner (in such a case, the scanner is a CCD camera). The identification of the two seal prints is conducted by the teller with human eyes. In other words, while the two images are overlapped with each other, the teller determines whether they are identical according to the image as displayed on the screen. If the pixels of the two images are overlapped to some extend, the two seal prints are considered identical; Otherwise, they are considered not identical.
Taiwan utility model registration No. 78873 relates to an "Image identification Platform" and discloses one of the semi-automatic seal print matching systems as described above. Although the semi-automatic systems can help the tellers to display the registered seal print in a very short time without the need to look up the seal print card, however, it is necessary for the teller to identify the seal print with human eyes. There is no objective criteria for the tellers to determine whether a seal print is genuine; All are decided based on experiences of the tellers. Especially when the seal print is printed by a counterfeit seal which is made by computerized imitation technology, a great amount of lose will happen to the bank.
It is then necessary for the industry to have an automatic seal print matching system that can match seal prints under objective criteria automatically.